Why is this medication prescribed?

Valacyclovir is used to treat herpes zoster (shingles) and genital herpes. It does not cure herpes infections but decreases pain and itching, helps sores to heal, and prevents new ones from forming.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Valacyclovir comes as a tablet to take by mouth. It is usually taken every 8 hours (three times a day) for 7 days to treat shingles. To treat genital herpes it is usually taken twice a day for 5 days. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take valacyclovir exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. Use this medication as soon as possible after symptoms appear.

Continue to take valacyclovir even if you feel well. Do not stop taking valacyclovir without talking to your doctor.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it, and take any remaining doses for that day at evenly spaced intervals. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Valacyclovir may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

headache

upset stomach

vomiting

diarrhea or loose stools

constipation

If you experience any of the following side effects, call your doctor immediately:

rash

itching

confusion

yellowness of the skin or eyes

fever

blood in the urine

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/Safety/MedWatch] or by phone [1-800-332-1088].

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to valacyclovir.

Do not have sexual intercourse when you can see the genital herpes lesions. However, genital herpes can be spread even when there are no symptoms.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription. If you still have symptoms of infection after you finish the valacyclovir, call your doctor.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.